Device for coupling a weaving shaft with a reciprocating drive lifter

ABSTRACT

The coupling device utilizes a toothed block on the heddle frame to engage a complementary toothed hook of a holder on the drive lifter in order to distribute the lifting and reciprocating forces between the cooperating surfaces. The block has two or more teeth with or without inclined sidewalls which mate within corresponding gaps of the holder.

United States Patent Pfarrwaller [451 Oct. 10, 1972 [54] DEVICE FOR COUPLING A WEAVING 2,256,572 9/1941 Pfarrwaller ..139/92 SHAFT WITH A RECIPROCATING 2,919,722 l/ 1960 Alford ..139/88 DRIVE LIFTER 3,074,438 1/ 1963 Svaty ..139/91 3,155,118 11/1964 Kaufmann ..139/91 [721 lnvemofl Pfarrwaller, Wmterthur. 3,406,726 10/1968 Pfarrwaller ..139/91 Switzerland [73] Assignee: Sulzer Brothers, Ltd., Winterthur, FOREIGN PATENTS OR APPLICATIONS Switzerland 1,221,421 1/ 1960 France ..139/57 1 9 Filed: Feb. 1969 465 526 2/1968 Switzerland 13 /57 [21 APP] 79 55 Primary Examiner-James Kee Chi Attorney-Kenyon & Kenyon Reilly Carr & Chapin [30] Foreign Application Priority Data 57] AB T ACT March 28, 1968 Switzerland ..4619/68 Th li d ice utilizes a toothed block on the heddle frame to engage a complementary toothed [52] US. Cl ..139/57, 139/91 hook of a holder on the drive lifter in order to di [5 1] Int. Cl ..D03c 13/00, D03c 9/06 tribute the lifting and reciprocating forces between the [58] Field of Search ..139/57, 55, 56, 58, 30, 31, cooperating surfaces. The block has two or more teeth 139/33, 82, 88, 91, 92 with or without inclined sidewalls which mate within corresponding gaps of the holder. [56] References Cited 10 Claims, 7 Drawing Figures UNITED STATES PATENTS 2,069,330 2/ 1937 Rossmann ..139/57 X PATENTEDnm 10 1972 EQW/N PFA LLEQ y/j IQTTOZNEY-S DEVICE FOR COUPLING A WEAVING SHAFT WITH A RECIPROCATING DRIVE LIFTER This invention relates to a device for coupling a heddle frame with a reciprocating drive lifter.

l-leretofore, it has been known to connect a heddle frame with a pair of drive lifters by installing a pair of block-shaped members in the weaving shaft and by providing the outer end of each lifter with a hook having two fork-like jaws which receive one of the members between them. The clearance between these assembly parts, i.e., the jaws and block-shaped members, has been made as small as possible so that the two jaws bear against the corresponding outer surfaces of the block-shaped members substantially uniformly.

However, even with very small clearance, it is possible for the parts in contact with one another to become slightly displaced during operation. After operating for a long time, this can produce wear so that the clearance between the individual part becomes increased. Through this shocks of relatively great magnitude can occur at the places of contact such that the blockshaped members or the hooks or both run out of true, thereby becoming useless prematurely. The parts must then be replaced or repaired.

Accordingly, it is an object of the invention to decrease the stressing of the contacting parts of a beddle frame and associated drive lifter.

It is another object of the invention to provide a coupling between a heddle frame and a drive lifter which will remain true during operation.

It is another object of the invention to increase the life of a heddle frame.

It is another object of the invention to increase the life of a coupling between a heddle frame and drive lifter.

Briefly, the invention provides a coupling device for coupling a heddle frame to a drive lifter which moves in a reciprocating vertical manner to raise and lower the heddle frame. The coupling device is constructed so as to minimize wear between the frame and lifter and to maintain the frame and lifter in balance. To this end, the coupling device consists of a toothed holder which is secured to the heddle frame and a toothed hook on the drive lifter which matingly engages with the holder. The holder is constructed of block-like shape with at least one recess in a side surface so as to form a pair of teeth and a tooth gap between the teeth. The hook is constructed with a similar configuration to have at least one tooth gap which receives a tooth of the holder and at least one tooth which is received in the holder. The surfaces or flanks of the mating teeth and gaps of the holder and hook are dimensioned to provide substantially large mating areas and are such that when the drive lifter moves in at least one direction of its reciprocating drive movement, at least two surfaces or flanks on each react against the load applied by the corresponding drive or reaction force. The force to be transmitted. during a drive movement of the lifter is thus transmitted into the holder through at least two engaging surfaces. Further, by dimensioning all the flanks with similar dimensions, double the contacting areas can be obtained in comparison to the formerly used weaving shaft couplings.

In one embodiment of the invention, the flanks of the respective tooth-gaps are made parallel with one another. With this shape, the contacting parts are particularly simple to fabricate and may be brought into engagement easily and be held easily in their operative position.

In another embodiment of the invention, the flanks of the respective tooth-gaps are inclined relative to one another in the direction in which the coupling parts are introduced into one another. With the contacting surfaces made in this way, the lifters and the holders can be brought into engagement with one another entirely without play, so that the heddle frame is driven almost completely free of shocks.

These and other objects and advantages of the invention will become more apparent from the following detailed description and appended claims taken in conjunction with the accompanying drawings in which:

FIG. 1 illustrates a general representation of a weaving shaft coupled to a pair of drive lifters according to the invention;

FIG. 2 illustrates an enlarged view of a coupling device of the invention;

FIG. 3 illustrates a view similar to FIG. 2 of a modified coupling device of the invention;

FIG. 4 illustrates a view of a holder of the invention in use with a conventional drive lifter;

FIG. 5 illustrates a view of another modified coupling device of the invention; v

FIG. 6 illustrates a view of still another modified coupling device of the invention; and

FIG. 7 illustrates a view taken on line 7-7 of FIG. 2.

Referring to FIG. 1, a heddle frame which can, for example, be installed in a loom or weaving machine and carried in lateral guides (not shown) includes a pair of frame beams 1,2 which are connected together at the ends by a pair of side bars 3,4. Each shaft beam 1,2 is made of a sheet steel hollow profile (cf. FIG. 7) and is provided with a plurality of rail supports 28 which serve to support a rail 29. The rails 29 which are also connected to the side bars 3,4 carry a plurality of flexible stranded wires (not shown) on which warp threads are carried.

The lower shaft beam 2 is carried on a pair of drive lifters 21 of hollow sheet metal profile. Each lifter 21 is guided vertically in a slideway guide 22 and a pin 23 which is installed inside the lower half of the lifter 21 is pivotally mounted in a push rod 24 to pivot in a plane parallel to the plane of the drawing, i.e., parallel to the shaft beams. The free end of the push rod 24 is articulated outside of the lifter 21 to an arm of a pivotal angle lever 25 which is mounted loosely on a shaft 26 secured in the machine frame (not shown). The second arm of the lever 25 is articulated to a guide bar 27 which is suitably connected to a drive shaft assembly (not shown) of the machine in order to be reciprocated horizontally as indicated by arrow 31 in the drawing.

Referring to FIG. 2, the coupling device for coupling the lower shaft beam 2 to the drive lifter 21 includes a surfaces 9,10 of the holder 5. The spacing between the flanks 12,13 amount to about one third of the height of the holder 5 while the gap 20 is centrally located on the side of the holder 5. In order to provide access to the holders 5, the beam 2 is formed with slots 14 in the narrow underside 8 beneath each holder 5.

In addition to a holder 5, each coupling device includes a hook 15 secured to the upper end of each lifter 21.. Each hook 15 has a toothing formed by two tooth gaps 11 and one tooth 19 with parallel flanks 17, 18 which are spaced apart a distance corresponding to the thickness of the holder tooth 30. Similarly, the thickness or height of the tooth 19 corresponds to the spacing between the flanks 12, 13 of the holder tooth gap 20. The tooth gaps ll, 20 are also of substantially the same depth so that the respective teeth 19, 30 are able to mesh completely in the coupled parts.

The dimensions of the parts brought into engagement are such that all four flanks l7, 18 of each hook l5 restuniformly against the tooth flanks, 9, 10, 12, 13 of a respective hook 15. As this necessitates a careful machining of these. parts, the edges 16 of the holder teeth 30 (FIG. 7) and the hook tooth 19 that are received in a gap are beveled.

In order to couple the heddle frame to the drive lifters, the lateral guide (not shown) which is associated with the side bar 4 is first removed. Next the heddle frame is guided from above and from the right as viewed in FIG. 1 to permit the hooks 15 to pass through the slots 15 into position adjacent the holders 5. Thence, the heddle frame is further moved to the left, as viewed, to mesh the holders 5 and hooks 15 together and to bring the weaving shaft into the lateral guide (not shown) associated with theside bar 3. Thereafter, the guide associated with the side bar 4 is reinstalled.

During operation the guide-bar 27 is set positively into motion, as shown by the arrows 31, by a driving machine, for example through'the intermediary of a double-cam. Consequently, the two lifters 21, through the intermediary of the angle-levers and the pushrods 24, move in correspondence with the arrows 32, so that the heddle frame makes the upward and downward movements needed to form the shed of the warp threads. The drive forces to be transmitted to the weaving-shaft are, at each movement of the lifters 21, thus imparted through the hooks 15 over two contact surfaces the outer surface 10 and the flank l2, and the outer surface 9 and the flank 13, respectively in the holders 5.

Referring to FIG. 3, wherein like reference characters have been used to indicate like parts as above, the heddle frame is provided with a holder 33 having three teeth and two tooth gaps 20. Similarly, each lifter 51 is provided with a hook 35 having three tooth gaps 11 corresponding in size to the holder teeth 30 and two teeth 19 corresponding in size to the holder gaps 20. In this construction, the drive forces of each lifter 51 are transmitted to the holder 33 by three contacting surfaces the outer surface 10 and the two flanks l2, and the outer surface 9 and the two flanks 13, respectively.

Referring to FIG. 5, wherein like reference characters are used to indicate like parts as above, each coupling device includes a holder 36 in the teeth 47 and a tooth-gap 37 between theteeth 47. The flanks 38, 41 and 39, 42 of the teeth 47 are further inclined in V-fashion toward one another. In addition, each lifter 53 is provided with a hook 40 which comprises two tooth-gaps 46 corresponding to the teeth 47- with correspondingly inclined flanks and a tooth 45 between the gaps 46 which is introducable into the holder toothgap 37.

Allthe inclined flanks are preferably at the same inclined angle. Also, in orderv to avoid stressing of the lateral guides of the heddle frame through horizontal components of the drive forces of the lifters 53, the angles of incline are made smaller than the angle of friction of the contacting parts. The hook 40 is therefore connected. in self-locking manner to the holder 36. With this type of construction, the parts that contact one another, regardless of the direction in which the lifters 53 are being driven, mesh particularly closely in one another.

Referring to FIG. 6, wherein like reference characters are used to indicate like parts as above, a holder 5 can alternatively mesh with a hook 48 of a lifter 54 that includes only one tooth gap 11 and one tooth 19. In this construction, the tooth 19 engages in the tooth gap 20 of the holder 5 while the hook 38 engages only the lower holder tooth 30.'Consequently, the drive forces of the lifter 54 during an upward movement are transmitted to the holder only through two contacting sur' faces, i.e., outer surface 10 and flank 12 while during downward movement, the force transmission is only through one contacting surface, i.e., the flank 13. Alternatively, the holder 5 can be arranged and the hook constructed so that only the upper tooth 30 is engaged by the hook.

Referring finally to FIG. 4, the holder 5 can also be utilized with existing weaving machines wherein the lifters 52 have hooks 34 defining only one recess with two walls 17', 18 but which are void of a tooth, such as a tooth 19 above. In this instance, by dimensioning the outer dimensions of the holder 5 (or holder 33 above described), it is possible to make use of the usual heddle frames having holders of approximately block shape by replacing such holders with the holders 5. However, as before, the drive forces of the lifters 52 are transmitted by such hooks 34 only through one contact surface, i.e., outer surface 9 or 10, to the holders 5.

It is'noted that in the case of weaving machines and looms that weave cloth of great width, or which, for example, work with heavy yams, the heddle frame can be coupled to more than two, for example, three, drive lifters. Also, the holders can be provided with more than two tooth gaps while the hooks are provided with a corresponding number of teeth engaging in the holder tooth gaps.

Further, it is noted that the coupling device of the invention can include a holder formed with a single tooth with two adjacent tooth gaps (or three teeth with the two tooth gaps therebetween) while the hook of a drive lifter is formed with a complementary meshing pair of teeth and a single tooth gap. This structure would function in a manner similar to that shown and described in FIG. 2 above.

What is claimed is:

l. A coupling device for coupling a heddle frame to a reciprocal drive lifter for driving the heddle'frame comprising a C-shaped holder secured on the heddle frame and defining at least one gap having a pair of flanks substantially transverse to the drive direction of the drive lifter and a hook secured on the drive lifter and defining a toothing having at least one tooth disposed within said gap of said holder and having surfaces resting on said flanks.

2. A coupling device as set forth in claim 1 wherein one of said holders and said hook has two teeth and a tooth gap therebetween, and wherein the other of said holder and said hook has one tooth and a pair of tooth gaps thereon in mating engagement.

3. A coupling device as set forth in claim 1 wherein said holder has said two teeth thereondefining said gap.

4. A coupling device as set forth in claim 1 wherein said flanks and said surfaces are parallel to each other.

5. A coupling device as set forth in claim 1 wherein said flanks and said surfaces are inclined.

6. A coupling device as set forth in claim 1 wherein said flanks and said surfaces are inclined at an angle less than the angle of friction of said holder and said hook.

7. A holder for a coupling device coupling a heddle frame to a reciprocal drive lifter, said holder being a metallic body of block shape and having a pair of teeth projecting from one side thereof to define a tooth gap therebetween.

8. A holder as set forth in claim 7 wherein said tooth .gap has a pair of opposed flanks formed on inclined angles less than the angle of friction of said body and directed inwardly towards each other.

9. A holder as set forth in claim 8 wherein each said tooth has an outer surface inclined on an angle less than said angle of friction opposite said adjacent flank.

10. A coupling device for coupling a heddle frame to a reciprocal drive lifter for driving the heddle frame comprising a holder secured on the heddle frame and defining at least one gap having a pair of flanks substantially transverse to the drive direction of the drive lifter and a hook secured on the drive lifter and defining a toothing having at least one tooth disposed within said gap of said holder and having surfaces resting on said flanks. 

2. A coupling device as set forth in claim 1 wherein one of said holders and said hook has two teeth and a tooth gap therebetween, and wherein the other of said holder and said hook has one tooth and a pair of tooth gaps thereon in mating engagement.
 3. A coupling device as set forth in claim 1 wherein said holder has said two teeth thereon defining said gap.
 4. A coupling device as set forth in claim 1 wherein said flanks and said surfaces are parallel to each other.
 5. A coupling device as set forth in claim 1 wherein said flanks and said surfaces are inclined.
 6. A coupling device as set forth in claim 1 wherein said flanks and said surfaces are inclined at an angle less than the angle of friction of said holder and said hook.
 7. A holder for a coupling device coupling a heddle frame to a reciprocal drive lifter, said holder being a metallic body of block shape and having a pair of teeth projecting from one side thereof to define a tooth gap therebetween.
 8. A holder as set forth in claim 7 wherein said tooth gap has a pair of opposed flanks formed on inclined angles less than the angle of friction of said body and directed inwardly towards each other.
 9. A holder as set forth in claim 8 wherein each said tooth has an outer surface inclinEd on an angle less than said angle of friction opposite said adjacent flank.
 10. A coupling device for coupling a heddle frame to a reciprocal drive lifter for driving the heddle frame comprising a holder secured on the heddle frame and defining at least one gap having a pair of flanks substantially transverse to the drive direction of the drive lifter and a hook secured on the drive lifter and defining a toothing having at least one tooth disposed within said gap of said holder and having surfaces resting on said flanks. 